76 



BULLETIN 



UNITED STATES NATIONAL MUSEUM. 



homologous element in the Elephas foot. It probably represents the articulation 

 for the much reduced and last phalanx of this digit. 



The principal measurements of these bones are as follows: 



Greatest transverse diameter 



Greatest antero-posterior diameter. 

 Greatest depth of posterior face 



Digit III. Digit IV, 



Of the other phalanges found associated with disarticulated feet, they appear 

 intermediate in form and deserve no especial mention. The fore foot is provided 

 with at least two flattened unguals, and though as yet not found articulated, un- 

 doubtedly belong to digits I and II. 



Fig. 41. — Dorsal view of unguals of Stegosaueus. 1, Ungual of hind foot. Cat. no. 7419, U.S.N. M. Juvenile 

 2, Ungu.il of digit I, forefoot. Cat. no. 4937, U.S.N.M, Type of Stegosaubus sulcatus Maksh. 3, Ungual of 



DIGIT I, FORE foot. CAT. NO. 7401, U.S.N.M. JUVTimLE. ALL FIGURES I N.AT. SIZE. 



These unguals are flattened, hoof-like bones that during the life of the animal 

 were doubtless incased in a horny nail. The specimens with which two unguals 

 have been found show that they are of two styles, one of which is as broad as long, 

 the other more elongated. The relative shape and size of these unguals are well 

 shown in figure 41. From the position in the rock of the elements pertaining to 

 the right fore foot of No. 4934, I am led to believe that the elongated ungual (1, 

 fig. 41) belongs to digit I. 



In old individuals the surfaces of these bones become very much roughened, 

 and the lateral, posteriorly directed points shown in figure 41, 1 and 3, continue 

 to ossify until they project posterior to the articular end as blunt rounded points 

 (fig. 41, 2). 



Belonging to the fore foot of No. 7401 are other elements which from their 

 close resemblance to some of the reduced terminal phalanges of Eleplms are con- 

 sidered the final ones of the remaining digits. Antero-posteriorly these are A^ery 



